1. Field of the Invention
This invention relates to a process for the homologation of methanol, or other lower alkanols, e.g. monohydroxy-C.sub.1 to C.sub.3 alkanols, into higher alkanols, i.e. alkanols having more carbon atoms than the starting alkanol, e.g. C.sub.2 to C.sub.4 alkanols, by contacting said lower alkanol with carbon monoxide, in the presence of a catalyst comprising a lanthanum moiety.
2. Description of the Art
There are various processes for preparing methanol, from carbon monoxide and hydrogen. For example, Magoon et al. in U.s. Pat. No. 3,758,417 teaches the preparation of methanol by reacting carbon monoxide and hydrogen, in the presence of a catalyst, comprising didymium in combination with copper and zinc. Bartley, in U.S. Pat. No. 4,312,955, discloses a lanthanum rhodate, having a perovskite structure, as a catalyst, for the same reaction.
Various references disclose the homologation of methanol with carbon monoxide and hydrogen in the presence of cobalt or rhodium catalysts. See patents to Taylor, i.e. U.S. Pat. Nos. 4,111,837 and 4,150,246, which disclose the homologation of alkanols in the presence of a catalyst system consisting essentially of cobalt carbonyl and rhenium metal. Slinkard et al., in U.S. Pat. No. 4,168,391, disclose an improved process for homologating methanol with carbon monoxide and hydrogen, in the liquid phase, and in the presence of a cobalt carbonyl catalyst. Bartish, in U.S. Pat. No. 4,171,461, also teaches the conversion of methanol to ethanol by reaction with hydrogen and carbon monoxide in the presence of a cobalt catalyst. In this invention, the improvement resides in the selection of the particular catalyst; however, it is clear that the catalyst must contain cobalt. Forrester, in U.S. Pat. No. 4,190,729, also teaches that a cobalt carbonyl catalyst is useful in the carbonylation of methanol to ethanol, acetaldehyde and methyl acetate. In this patent the improvement resides in using a tertiary phosphine oxide as a stabilizer for the cobalt carbonyl catalyst. Hargis et al., in U.S. Pat. Nos. 4,309,314 and 4,361,499, disclose reacting methanol with hydrogen and carbon monoxide, in the presence of catalyst comprising rhodium and iron, to provide ethanol and methyl acetate. This catalyst may also comprise a minor amount of an alkaline metal or a heterocylic amine promoter to enhance the formation of a substantial portion of ethanol and methyl acetate. A tertiary amine is used as a promoter in Feder et al., U.S. Pat. No. 4,386,009, wherein the conversion of methanol to ethanol, by reaction with carbon monoxide and hydrogen, is disclosed. Finally, Kummer et al., U.S. Pat. No. 4,454,358, teach that ethanol may be produced, continuously, by the carbonylation of methanol with carbon monoxide and hydrogen, in the presence of a Group VIII carbonyl catalyst and a halogen compound. In the processes disclosed in the above references, extensive quantities of hydrogen are undesirably consumed.
In one reference, Schultz, U.S. Pat. No. 3,717,670, it is taught that alcohols may be reacted with carbon monoxide, in the presence of a catalyst comprising a rhodium component, in combination with a metal compound selected from the IB, IIB, IVB, VB, VIB and VIII, lathanide and actinide groups of the Periodic Table of the Elements, to provide organic acids and organic esters. This reference indicates that a halide promoter is a necessary component of the catalyst. The process disclosed in reference is carried out in the absence of hydrogen; however the reaction product is acetic acid, not a higher alcohol.
Accordingly, it is an object of this invention to provide an improved process for homologation of alkanols with carbon monoxide.
It is another object of this invention to provide a novel heterogenous catalyst adapted for conversion of methanol to ethanol and higher alkanols.
It is a further object of this invention to provide a process for preparing an improved catalyst system for the liquid phase homologation of alkanols.
Other objects and advantages of this invention shall become apparent from the following description and exemplary data.